Floor polishing machine

Abstract

A floor polishing machine according to the preferred form of the teachings of the present invention includes a body portion having a platform, and a handle pivotally mounted to the platform. First and second sets of wheels are provided adjacent the rear of the platform and on opposite sides of the handle pivot. For coupling the handle and the platform together, torsion springs are provided having first ends anchored to the platform and having second ends connected to the handle. The torsion springs urge the platform to pivot about the first set of wheels downwardly in the rear and upwardly in the front. The level of the second set of wheels is slightly above the level of the first set of wheels for limiting the amount of upward movement of the front of the platform by the torsion springs when the polishing member is not being rotated by the motor allowing a partial vacuum to be formed under the polishing member when it is rotated by the motor to place a downward suction on the polishing member and counteracting with the torsion springs to place an even force on the floor surface by the polishing member regardless of the pivotal position of the handle with respect to the platform and regardless of the unevenness of the floor surface.

What is claimed is: 
     
       1. Machine for polishing floor surfaces comprising, in combination: a body portion adapted to be moved along the floor, with the body portion including a platform having a front and a rear; a polishing member mounted for rotation about a polishing axis within the body portion for polishing the floor surface when the body portion is moved along the floor; a handle for guiding and controlling the movement of the body portion along the floor, with the handle being pivotally mounted to the platform about a pivot axis for movement between operating positions and a transport position; a first set of wheels rotatably mounted adjacent the rear of the platform and between the handle pivot axis and the polishing axis for supporting the platform above the floor surface; torsion spring means between the handle and the platform for urging the platform to pivot about the first set of wheels when the handle is in an operating position such that the rear of the platform moves downwardly and the front of the platform moves upwardly; and a second set of wheels located at the rear of the platform and on the opposite side of the first set of wheels than the polishing axis, with the level of the second set of wheels being higher than the first set of wheels for limiting the amount of upward movement of the front of the platform by the torsion springs when the polishing member is not being rotated in the body portion allowing a partial vacuum to be formed under the polishing member when the polishing member is initially rotated in the body portion to place a downward suction on the polishing member and counteracting with the torsion springs to place an even polishing force on the floor surface by the polishing member regardless of the pivotal position of the handle with respect to the platform and regardless of the unevenness of the floor surface. 
     
     
       2. The floor polishing machine of claim 1 wherein the pivot axis of the handle is intermediate the first and second set of wheels. 
     
     
       3. The floor polishing machine of claim 2 wherein said torsion spring means includes first and second torsion springs, with the torsion springs having first ends and second ends; and wherein the floor polishing machine further comprises, in combination: means for anchoring the first ends of the torsion springs to the platform; and means for connecting the second ends of the torsion springs to the handle, with the torsion springs being located concentrically about the pivot axis of the handle and on opposite sides of the handle. 
     
     
       4. The floor polishing machine of claim 3 wherein the anchoring means comprises, in combination: a boss secured to the platform adjacent each of said first ends; and a bolt threadably received in each of the bosses, with each of the first ends of the torsion springs abutting with said bolts. 
     
     
       5. The floor polishing machine of claim 3 wherein the connecting means comprises a connection member interconnected between the second ends of the first and second torsion springs, with the connection member abutting with the handle above the pivot axis of the handle. 
     
     
       6. The floor polishing machine of claim 1 wherein the handle has an end; and wherein the floor polishing machine further comprises, in combination: means for locking the handle in its transport position comprising, in combination: a plug reciprocally received in the end of the handle; and a catch secured to the platform and complementary to the plug for removably attaching the plug to the catch. 
     
     
       7. Machine for polishing floor surfaces comprising, in combination: a platform having a front and a rear; a first set of wheels rotatably mounted along a generally horizontal wheel axis adjacent the rear of the platform for supporting the platform above the floor surface; a polishing member rotatably mounted to the platform for rotation about a generally vertical axis and means for rotating the polishing member about the vertical axis; a handle pivotally mounted to the platform about a generally horizontal pivot axis located on the opposite side of the wheel axis than the vertical axis of the polishing member; means for coupling the handle and the platform for pivoting the platform about the wheel axis of the first set of wheels with the rear of the platform being biased in a downward direction and the front of the platform being biased in an upward direction; and means located at the rear of the platform and on the opposite side of the wheel axis than the vertical axis of the polishing member for limiting the amount of upward movement of the front of the platform by the coupling means when the polishing member is not being rotated by the rotating means allowing a partial vacuum to be formed under the polishing member when the polishing member is initially rotated by the rotating means to place a downward suction on the polishing member and counteracting with the coupling means to place an even force on the floor surface by the polishing member regardless of the pivotal position of the handle with respect to the platform and regardless of the unevenness of the floor surface. 
     
     
       8. The floor polishing machine of claim 7 wherein the first set of wheels space the rear of the polishing member from the floor surface. 
     
     
       9. The floor polishing machine of claim 8 wherein the first set of wheels space the rear of the polishing member from the floor surface such that the front two-thirds of the polishing member engage the floor surface when the polishing member is rotated by the rotating means. 
     
     
       10. The floor polishing machine of claim 8 wherein the first set of wheels space the entire polishing member from the floor surface when the polishing member is not being rotated by the rotating means. 
     
     
       11. The floor polishing machine of claim 7 wherein the handle is pivotally mounted to the platform between operating positions and a transport position; and wherein the limiting means also enables the transport of the platform and polishing member over the floor surface when the handle is in the transport position. 
     
     
       12. The floor polishing machine of claim 11 wherein the limiting means comprises a second set of wheels extending at a level slightly above the level of the first set of wheels. 
     
     
       13. The floor polishing machine of claim 12 wherein the level of the second set of wheels is in the range of 1/8 to 1/4 inches above the level of the first set of wheels. 
     
     
       14. The floor polishing machine of claim 11 wherein the handle has an end; and wherein the floor polishing machine further comprises, in combination: means for locking the handle in its transport position comprising, in combination: a plug reciprocally received in the end of the handle; and a catch secured to the platform and complementary to the plug for removably attaching the plug to the catch. 
     
     
       15. The floor polishing machine of claim 7 wherein the coupling means comprises, in combination: means for urging the front of the platform towards the handle. 
     
     
       16. The floor polishing machine of claim 15 wherein the urging means comprises at least a first torsion spring. 
     
     
       17. The floor polishing machine of claim 15 wherein the urging means comprises, in combination: first and second torsion springs having first ends and second ends, with the torsion springs being located concentrically about the pivot axis of the handle and on opposite sides of the handle; means for anchoring the first ends of the torsion springs to the platform; and means for connecting the second ends of the torsion springs to the handle. 
     
     
       18. The floor polishing machine of claim 17 wherein the anchoring means comprises, in combination: a boss secured to the platform adjacent each of said first ends; and a bolt threadably received in each of the bosses, with each of the first ends of the torsion springs abutting with said bolts. 
     
     
       19. The floor polishing machine of claim 17 wherein the connecting means comprises a connection member interconnected between the second ends of the first and second torsion springs, with the connection member abutting with the handle above the pivot axis of the handle. 
     
     
       20. The floor polishing machine of claim 7 wherein the pivot axis of the handle is intermediate the wheel axis of the first set of wheels and the limiting means.